RE: [Caml-list] Newbie comment on constructor syntax

["Soegtrop, Michael" <michael.soegtrop@intel.com>]

Dear Florian, Norman, 

> > Curiously, the argument is not really a tuple.  This does not work:
> >
> > type x = X of int * int
> > let c = (1, 2) in X c
> 
> However the following works:
> # type x  = X of (int * int);;
> type x = X of (int * int)
> # let c = (1, 2) in X c;;
> - : x = X (1, 2)

Exactly this is what is quite confusing (for the beginner): constructors are a rather odd mix of multiple arguments and tuples. The notation looks like tuples, both in definition and use, but it isn't. And it is not a multiple argument function either, since currying doesn't work. That adding parenthesis makes it a real tuple doesn't make it better, since at some other places a*b and (a*b) are the same.

To me this is quite a scar in the beauty of the language - the kind of thing you can't avoid to look at, if you know what I mean. Of cause it is not really an issue. It is just way disappointing for new users to find this kind of imperfection and it gives a little dent in the enthusiasm. But just a little one ;-)

Best regards,

Michael

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